Announcements

This Web site provides information on the process EPA, the states and the tribes engage in to designate areas as "attainment" (meeting) or "nonattainment" (not meeting) the 24-hour PM2.5 standards established in 2006.

The Clean Air Act requires EPA to issue designations after the agency sets a new National Ambient Air Quality Standard (NAAQS) or revises an existing standard. EPA formally designates areas as “nonattainment” (not meeting the standard), “unclassifiable/attainment” (meeting the standard or expected to be meeting the standard despite a lack of monitoring data), or “unclassifiable” (insufficient data to classify).

Once nonattainment designations take effect, the state and local governments have three years to develop implementation plans outlining how areas will attain and maintain the standards by reducing air pollutant emissions contributing to fine particle concentrations.

EPA strengthened the air quality standards for particle pollution in 2006. Designations will take effect in 2009.

This Web site contains the following information:

State Designations:
EPA has determined compliance with the 24-hour fine particle (PM2.5) standard. The status of this effort is summarized here.

Tribal Designations:
EPA has determined compliance with the 24-hour fine particle (PM2.5) standard. The status of this effort is summarized here.

Frequent Questions: Answers to common questions regarding
fine particles and the designations process.

Technical Information: Data and tools for States and Tribes that may be useful in the 24-hour PM2.5 NAAQS designation process.

PM2.5 Conditions: Links
to the AirNOW Web site with real-time information on PM2.5 conditions and web cameras around the country.

Air Quality Forecast: Links to the Air NOW Web site with PM2.5 air
quality forecasts for dozens of cities around the country.